1. Field of the Invention
The present invention generally relates to networking and, more particularly, to method for transitive Authentication Authorization and Accounting (AAA) in the interworking between access networks.
2. Background of the Invention
Typically, Authentication, Authorization and Accounting (AAA) are required to access and utilize networks such as cellular networks and Wireless Local Area Networks (WLANs). In an environment in which a mobile terminal has multiple network access mechanisms, providing AAA interworking among these networks is of great importance. However, it is generally the case that one or more of the involved networks have a closed AAA scheme and it is difficult for one of the networks to use the AAA structure of another one of the networks and vice versa. For example, cellular networks have an AAA infrastructure that is not compatible with Internet based AAA and cannot be easily accessed through Internet protocols, even though the involved networks (including the cellular networks) have external IP connectivity.
Convention approaches for providing AAA interworking all require a special interworking function between the networks, even for AAA interworking between networks that have pre-established trust relationships amongst themselves. Using this interworking function, e.g., network B will then access network A's AAA infrastructure to authenticate a user which has already been authenticated by network A (through a closed network AAA mechanism). The conventional approaches do not take advantage of the fact that the user has already been authenticated by network A which has pre-established trust relationship with network B.
Accordingly, it would be desirable and highly advantageous to have a method for transferring the trust that is attributed to a user by one network from that network to another network, particularly without requiring any special interworking function to accomplish the same.